Beverage capsules comprise a hollow container portion that houses a dose of at least one extractable or reconstitutable product, generally ground coffee, but also tea herbal extracts, instant i.e. powdered drinks and liquid concentrates, are known in the art. The capsules also comprise a portion that interacts with a brewing device to prepare the required beverage. The typical brewing device comprises water heating means, an enclosing member, or receptacle, intended to cooperate with the capsule to define a preparation chamber and a pump or similar means so that the brewing liquid, usually but not exclusively hot water under pressure, can be supplied to the capsule for the extraction or reconstitution of the beverage from the dose of product contained therein.
The enclosing member, or receptacle, is usually movable with respect to the capsule, or vice versa, between an open position in which the capsule can be inserted into the brewing device and a closed position wherein the capsule is at least in part housed inside the receptacle. The receptacle is further provided with a circular pressing edge, intended to cooperate with the capsule, and in particular with a flange-like rim extending from the capsule, in order to form a seal tight engagement.
Therefore the capsule needs to be dimensioned so that it can be inserted into the brewing device, and to avoid undesired contacts between the capsule and in particular the inlet wall of the capsule with the receptacle, and in particular with its circular pressing edge.
Additionally, the capsule needs to be dimensioned so that it can be housed in the receptacle when the latter is moved towards the closed position.
At the same time the dimension of the capsule, and in particular the internal volume of its hollow body, must be able to contain a certain amount of extractable product, for example coffee powder, in order to obtain the desired quality and quantity of the brewed beverage. Therefore there is the need of maximizing the volume of the capsule while taking into account the dimension of the brewing device, and in particular the height of the capsule need to be dimensioned so that the capsule can be inserted into the brewing device.
Additionally, it has to be noted that in known brewing device the capsule is inserted into the brewing device with its central axis inclined with respect to the axis along which the receptacle is movable between the open and closed position.
Therefore, also the relative position between the capsule and the receptacle needs to be taken into account when the capsule is dimensioned.
In a known beverage preparation process, a capsule is fed into the receptacle of the brewing device and is fed with the brewing liquid, such as hot water.
The injected brewing liquid passes through the capsule and thus creates by dissolving the soluble solids contained in the foodstuff or solubilizing the powder contained in the capsule or otherwise diluting the liquid concentrate contained therein. In other words the injection of the brewing liquid inside the capsule allows for the constitution of the beverage from the ingredient enclosed therein. The beverage thus formed exits the capsule to reach a beverage collector or outlet spout and thence a cup or a container.
In the following description reference will be made to coffee preparation with hot water, this disclosure is exemplary and the scope of the present invention is not limited to coffee preparation with hot water.
It is known to provide open capsule, having the inlet wall (or inlet surface) and optionally the outlet wall (or outlet surface) of the capsules provided with holes to feed water inside the capsule. It is also known to utilize capsules in which the inlet wall and the outlet wall of the capsule are closed, i.e. the capsule body is in general a closed body, so that the coffee powder cannot be spilled out during handling or transport and the oxidation of the coffee powder is reduced.
Both “open” and “closed” capsules need to be dimensioned in order to maximize the internal volume and also allowing their easily and effective insertion inside the receptacle of the brewing devices.
Additionally, in order to open closed capsules, the brewing device is provided with piercing means, usually in the form of one or more protruding blades or perforators, intended to contact and to perforate the inlet wall and/or the outlet wall of the capsule. Apertures, or holes, formed by the piercing means allow the passage of the brewing liquid inside the capsule form the inlet wall and/or the extraction of the prepared beverage form the outlet wall.
Feeding of brewing hot water by piercing the inlet wall of the capsule is a method well known in the art and is disclosed in several prior art documents.
Recently, some problems have been encountered by using capsule made of plastic polymers instead of capsule made of more rigid material, such as aluminium. Capsules made of plastics can be difficult to perforate because of shapes of the piercing means that have been studied for use with aluminium only; as a result, full piercing of the capsule wall is not achieved, thereby no or not enough hot water can be injected in the capsule, or only a partial perforation is achieved, thus providing an irregular and unsatisfactory distribution of the brewing liquid inside the capsule and equally irregular quality of the beverage in the cup. For facilitating the perforation by piercing means of the brewing device plastic capsules have been provided with reinforcing members. However, the known solutions require a higher mass of thermoplastic material during the production process, resulting in a heavier, less environmental-friendly capsule.
Additionally, in some cases different brewing devices, provided with piercing means shaped in different manner, cannot achieve the perforation and in some cases the shape of the inlet wall and/or the presence of reinforcing means leads to an undesired reduction of the internal volume of the capsule wherein the dose of product is contained. A lower amount of the product contained inside the capsule inevitably leads to an unsatisfactory quality of the beverage obtained during the brewing process.
It is an aim of the present invention, to provide a capsule and a system for the beverage preparation using such capsule, allowing the maximization of the internal volume of the capsule body, in both “open” and “closed” capsules, in order to increase the quantity of product contained therein, thus increasing the quality of the prepared beverage.
At the same time, an aim of the present invention is to provide a capsule that can be easily inserted into the beverage preparation device, thus avoiding that the capsule is blocked inside the brewing device.
It is a further aim of the present invention to provide a capsule and a system for the beverage preparation using such capsule, allowing an effective perforation with piercing means belonging to different brewing devices and shaped in different manner. Another aim of the present invention is to provide a capsule that can be effectively used in different types of beverage preparation device, provided with different piercing means. Summary of the invention